Learning Objectives: The goal of this educational exhibit is to provide an overview of treatment response guidelines relevant to interventional radiologists. Being familiar with organ specific and non-organ specific treatment response evaluation guidelines is crucial for optimal assessment and planning for subsequent therapies. Background: Imaging-based evaluation of tumor response is an important aspect of oncology. Most treatment modalities offered by interventional radiologists are cytostatic in nature and do not necessarily cause a decrease in size of neoplasm in response to treatment. Interventional radiologists should be familiar with response evaluation guidelines for optimal assessment of response. Clinical Findings/Procedure Details: Different imaging guidelines for evaluation of treatment response are discussed with emphasis on those most relevant to interventional radiologists. An overview of anatomical imaging biomarkers of treatment response such as WHO and RECIST guidelines and volumetric evaluation is provided. Functional biomarkers of treatment response such as PET will be reviewed. Liverspecific biomarkers of treatment response such as mRECIST, EASL and Choi criteria will be discussed. Conclusions: A brief overview of imaging biomarkers of treatment response is provided to ensure optimal assessment and planning in interventional oncology.
References1. Salem R, Thurston KG. Radioembolization with 90Yttrium microspheres: a state-of-the-art brachytherapy treatment for primary and secondary liver malignancies. Part 1: Technical and methodologic considerations. J Vasc Interv Radiol 2006; 17(8):1251-1278. 2. Tochetto SM, Rezai P, Rezvani M, et al. Does multidetector CT attenuation change in colon cancer liver metastases treated with 90Y help predict metabolic activity at FDG PET? Radiology 2010; 255(1):164-172. 3. Galizia MS, Tore HG, Chalian H, McCarthy R, Salem R, Yaghmai V. MDCT necrosis quantification in the assessment of hepatocellular carcinoma response to yttrium 90 radioembolization therapy: comparison of twodimensional and volumetric techniques. Acad Radiol 2012; 19(1):48-54. 4. Yaghmai V, Miller FH, Rezai P, Benson AB, 3rd, Salem R. Response to treatment series: part 2, tumor response assessment-using new and conventional criteria. AJR Am J Roentgenol 2011; 197(1):18-27. Educational Exhibit Abstract No. 572 Percutaneous gallbladder ablation: from boiling contrast to cryotherapy-what we have learned and have yet to discover